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Slingsby Primary

Dagnali-designed training glider

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionJul 25, 2026
Entity authorityQ1434150
Source-derived summary

The Slingsby T.3 Primary (a.k.a. Dagling) was a single-seat training glider produced in the 1930s by Fred Slingsby in Kirbymoorside, Yorkshire.

Design and development

During the 1920s Alexander Lippisch designed a training glider with very low performance to introduce pilots gradually to full-blown gliding. The result was a glider with a very simple structure of an open framework fuselage, with short wings attached by cables to a king post and the base of the fuselage. Lippisch's original design, the Zögling (Pupil in English) had an all-wood fuselage but Wolf Hirth instigated a redesign of the rear fuselage using steel tubes.

History

The plans for the modified Zögling made their way via the United States to the London Gliding Club and Reginald Foster Dagnall, whose RFD company put it into production as the RFD Primary. They built 27 in 1930–31. The type became known as the Dagling, a name formed by combining Dagnall and Zögling, which later came to be used informally to cover all types of primary gliders in the UK. Fred Slingsby took over construction in 1934 and production continued up to the outbreak of World War II. The Primary should not be confused with the similar T.38 Grasshopper which was produced for the Air Training Corps in the 1950s.

Operators

Variants

Slingsby T.3 Primary

Derived from the Wolf Hirth-modified Zögling

RFD Primary Type AT

Production of the Primary by the R.F.D. Co, named Dagling from a contraction of Dagnall and Zögling.

Hawkridge Dagling

A modified Dagnall built post-World War II by the Hawkridge Aircraft Co.

Editorial summary

“Slingsby Primary” enters the record as dagnali-designed training glider. Crown Archives preserves that source wording while asking what Slingsby, Primary and Dagnali-designed can confirm, complicate or overturn.

Editorial reviewA concise reference frame for defining the subject, testing terminology and identifying the institution closest to the evidence. The current lead gives the account dated anchors—1930, 1934—that can be checked directly. The selected authority fields contribute no independent date. Its strongest next move is a source search built around Slingsby, Primary and Dagnali-designed.
Editorial analysis

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“Slingsby Primary” is worth following because a concise public description often conceals a longer documentary argument. Here, Slingsby, Primary and Dagnali-designed provides the most credible route into that argument.

Evidence profile

Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated Jul 25, 2026. The linked authority identifier is Q1434150. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1930 and 1934.

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A concise general-reference account can conceal disagreements about scope, terminology or the weight assigned to individual sources. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

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Source & attribution

This entry incorporates text from Slingsby Primary” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.